Disentangle assembler from isolate.

src/ia32/assembler-ia32-inl.h

Index: src/ia32/assembler-ia32-inl.h
diff --git a/src/ia32/assembler-ia32-inl.h b/src/ia32/assembler-ia32-inl.h
index 7647bc18e7dcff88dddb4fecb9ae2b590f6655f0..f9f1dc920d6b923b9ce125557a433c7e9e6b7349 100644
--- a/src/ia32/assembler-ia32-inl.h
+++ b/src/ia32/assembler-ia32-inl.h
@@ -117,7 +117,7 @@ void RelocInfo::set_target_object(HeapObject* target,
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
   Memory::Object_at(pc_) = target;
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
-    Assembler::FlushICache(isolate_, pc_, sizeof(Address));
+    Assembler::FlushICache(target->GetIsolate(), pc_, sizeof(Address));
   }
   if (write_barrier_mode == UPDATE_WRITE_BARRIER && host() != NULL) {
     host()->GetHeap()->RecordWriteIntoCode(host(), this, target);
@@ -150,13 +150,12 @@ Address RelocInfo::target_runtime_entry(Assembler* origin) {
   return reinterpret_cast<Address>(*reinterpret_cast<int32_t*>(pc_));
 }
 
-
-void RelocInfo::set_target_runtime_entry(Address target,
+void RelocInfo::set_target_runtime_entry(Isolate* isolate, Address target,
                                          WriteBarrierMode write_barrier_mode,
                                          ICacheFlushMode icache_flush_mode) {
   DCHECK(IsRuntimeEntry(rmode_));
   if (target_address() != target) {
-    set_target_address(target, write_barrier_mode, icache_flush_mode);
+    set_target_address(isolate, target, write_barrier_mode, icache_flush_mode);
   }
 }
 
@@ -182,7 +181,7 @@ void RelocInfo::set_target_cell(Cell* cell,
   Address address = cell->address() + Cell::kValueOffset;
   Memory::Address_at(pc_) = address;
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
-    Assembler::FlushICache(isolate_, pc_, sizeof(Address));
+    Assembler::FlushICache(cell->GetIsolate(), pc_, sizeof(Address));
   }
   if (write_barrier_mode == UPDATE_WRITE_BARRIER && host() != NULL) {
     host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(host(), this,
@@ -209,8 +208,9 @@ void RelocInfo::set_code_age_stub(Code* stub,
                                   ICacheFlushMode icache_flush_mode) {
   DCHECK(*pc_ == kCallOpcode);
   DCHECK(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);
-  Assembler::set_target_address_at(
-      isolate_, pc_ + 1, host_, stub->instruction_start(), icache_flush_mode);
+  Assembler::set_target_address_at(stub->GetIsolate(), pc_ + 1, host_,
+                                   stub->instruction_start(),
+                                   icache_flush_mode);
 }
 
 
@@ -220,11 +220,10 @@ Address RelocInfo::debug_call_address() {
   return Assembler::target_address_at(location, host_);
 }
 
-
-void RelocInfo::set_debug_call_address(Address target) {
+void RelocInfo::set_debug_call_address(Isolate* isolate, Address target) {
   DCHECK(IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence());
   Address location = pc_ + Assembler::kPatchDebugBreakSlotAddressOffset;
-  Assembler::set_target_address_at(isolate_, location, host_, target);
+  Assembler::set_target_address_at(isolate, location, host_, target);
   if (host() != NULL) {
     Code* target_code = Code::GetCodeFromTargetAddress(target);
     host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(host(), this,
@@ -232,14 +231,13 @@ void RelocInfo::set_debug_call_address(Address target) {
   }
 }
 
-
-void RelocInfo::WipeOut() {
+void RelocInfo::WipeOut(Isolate* isolate) {
   if (IsEmbeddedObject(rmode_) || IsExternalReference(rmode_) ||
       IsInternalReference(rmode_)) {
     Memory::Address_at(pc_) = NULL;
   } else if (IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)) {
     // Effectively write zero into the relocation.
-    Assembler::set_target_address_at(isolate_, pc_, host_,
+    Assembler::set_target_address_at(isolate, pc_, host_,
                                      pc_ + sizeof(int32_t));
   } else {
     UNREACHABLE();
@@ -434,6 +432,7 @@ Address Assembler::target_address_at(Address pc, Address constant_pool) {
 void Assembler::set_target_address_at(Isolate* isolate, Address pc,
                                       Address constant_pool, Address target,
                                       ICacheFlushMode icache_flush_mode) {
+  DCHECK_IMPLIES(isolate == nullptr, icache_flush_mode == SKIP_ICACHE_FLUSH);
   int32_t* p = reinterpret_cast<int32_t*>(pc);
   *p = target - (pc + sizeof(int32_t));
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {